UFC: What Is the Cause of Premature Retirements and Hiatuses?

Martin Kampmann, welterweight warrior and one of the goriest, gutsiest performers in the history of the sport, is "on hiatus" according to what he told MMA Junkie this week.

The Dane seems likely to come back, something fans will no doubt rejoice over when it happens given his propensity for putting on jaw-dropping fights, but he's done for now.

Throw him in there with Georges St-Pierre, Nick Diaz, Donald Cerrone, Jon Jones and Ronda Rousey as a big name that has either hinted at going home for a bit or outright done it in the past few months.

Quinn Mulhern and Julie Kedzie are also on the list, though with less fanfare, and it leads to a big question: What's going on in MMA that's causing these young guys (and gals) to pack it in?

St-Pierre and Kedzie are the oldest in the group by far, and they're 32 years old. That's a startlingly young age to give up anything, much less a fairly lucrative career—St-Pierre as the world's top draw, and Kedzie as a long-suffering female fighter who was finally in the big show—and it has to make one wonder.

The most logical argument centers around the fact that MMA is a gladiatorial pursuit at its core. You can put up a fence, flash some lights around and do the whole thing under the watchful eye of an athletic commission, but it's still two people smashing each other's faces in at the end of the day.

That's not easy for someone to do once, much less dozens of times in a condensed frame during the prime of their lives. If it was, there would be a lineup of street fights a mile long on every corner in the country.

There's also the training, presently being documented by our own Duane Finley in his trek across America, to grind away at a fighter's soul. The hours toiling at battle ropes and kettle bells, eating head kicks from training partners instead of dinner with the family and spilling blood and sweat like they're commodities without value.

It's a burden to carry. It's one that fighters choose to carry, but a burden nonetheless.

And what of the mental side of the game? Sure the miles add up physically, but the toll on the mind has to be significant too.

To push oneself to the outer limits of will on a daily basis only to be locked in a cage with a trained killer, your skills and Kim Winslow the only things to stop it from happening?

For every piece of Internet hate, Twitter soapbox or well-considered critique that comes every time that door shuts, that is mixed martial arts at its basest reality: You could die in there any time.

Think of the weight that would have on a human mind. No wonder these athletes need a break from time to time.

This isn't to say that the sport is barbaric and horrible, that it needs to be regulated to the point that fight night becomes exclusively open-handed strikes in full pads. We all like an element of risk in life, and MMA is a sport that treads that ground in the same way hockey or football does.

But to not ask questions while some of the best athletes in the world leave the sport before they've even entered their prime, or while they're right in the midst of it, is irresponsible. It's enjoying the blood on the canvas without asking what the cost was.

This week the UFC lost another great combatant to the lure of life away from the fight, a trend that seems to be growing. This is a sport that is in no way for the feint of heart, and that applies to those who pursue its glories as well.

Times like these serve as prime chances to remember that and to be appreciative of it.